Improvement in inks for printing stamps, drafts, and checks



1 "near 595mm fitment cam.

Letters Patent No. 101,170, dated March 22, 1870.

IMPROVEMENT IN INKS FOB PRINTING STAMPS, DRAFT-S, AND CHECKS.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern and exact description of the same.

This invention is more especially intended to prevent the erasure or removal, without detection, of the signatures, amounts, and other written portions, or the cancellations or other supcrscriptionsfrom all such articles, documents, or matters as'I have above enumerated; and the system which I adopt for this purpose, and upon which my invention is based, is the employ-, ment, for printing a tint in oil-colors on the faces of such articles, documents, or matters, of an ink, the color of which will be removed or changed by acids or other chemicals that may be employed for the removal of the written or other superscription.

The invention consists in an ink in which orchil is employed in combination with the ordinary composition or menstruum forming the basis of or uscd in inks for printing tints in oil-colors.

The proportions of the materials employed may b varied considerably without materially affecting the character of my invention, but I will here give the formula of an ink which I have used with great success, the proportions being all by weight:

Zinc white or Paris white, six (6) parts; magnesia, one (1) part; beeswax, one (1) part; printers varnish, three (3) parts; spirits turpentine, one (1) part; orchil, two (2) parts.

These materials are ground together and thoroughly incorporated, and the ink produced is used in the same way as any other oil printing-ink.

Tints or devices printed with this ink are changed in color or destroyed entirely by any acid or chemical that can be used to remove ordinary writing, and, in this respect, it differs from all other oil printingflnks now used.

What Iclaim as my invention, and desire to secure by Letters Patent, is-

The combination of orchil with a printing-ink, substantially as and for the purpose herein described.

Witnesses: JOHN P. SIMON DS,

FRED. HAYNES, HENRY PALMER. 

